From what I know, Uni Mannheim prides itself as one of the best Economy focused universities in Germany. My dad graduated from Mannheim in the 90s, although not from the MBA program. He is currently running his own business in China importing medical equipment from Germany.
I consider Mannheim my home town although I was born in China. I wouldn't consider Mannheim close to Germany's business district, although it is surrounded by some extremely influential businesses, such as BASF Chemicals, SAP and it's only 45 minutes from Frankfurt.
I would consider going back as well, but I'm living in London at the moment and there are also quite a few top ranked MBA programs over here.
Staying positive and having fun with the GMAT.
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